Great light - SureFire M300 Mini Scout Light LED Flashlight

I have this light on several guns, it's compact while and plenty powerful. It is definitely ideal for short barrel pistols or SBRs as it's easier to get it out of the way and clear up your rail. You'll probably want to add a pressure pad too which is going to run you and additional $86 for the basic setup and $158 for the more tailcap with the on/off switch for constant light. The stock mount is fine for mounting on picatinny but your going to need something else for wither keymod or m-lock. Arisaka makes good options for around $45.

I don't think you'll regret purchasing this light and would recommend it.